Liquid-crystal display devices that use liquid crystal and plasma display devices that use plasma have found practical application as flat and thin display devices.
A liquid-crystal display device provides a backlight, and displays images by altering an array of liquid-crystal molecules by application of voltage, passing or blocking light from the backlight. Additionally, a plasma display device causes a plasma state to occur by application of voltage to a gas enclosed within a substrate to assume, and ultraviolet light produced by energy occurring on return from the plasma state to the original state becomes visible light through emission to a fluorescent material, displaying an image.
Meanwhile, in recent years, development has been progressing for self-illuminating displays employing organic EL (electroluminescent) elements in which the element itself emits light when voltage is applied. When the organic EL element receives energy by electrolysis, it changes from a ground state to an excited state, and at the time of return from the excited state to the ground state, the energy difference is emitted as light. The organic EL display device is a display device that displays images using the light emitted by these organic EL elements.
A self-illuminating display device, unlike a liquid-crystal display device, which requires a backlight, requires no backlight because the elements themselves emit light, and so it is possible to make the structure thin compared to a liquid-crystal display device. Additionally, because motion characteristics, viewing-angle characteristics, color-reproduction performance, and the like are excellent compared to a liquid-crystal display device, organic EL display devices are attracting attention as next-generation flat and thin display devices.
However, in an organic EL element, light-emission characteristics deteriorate when application of voltage is continued, and luminance declines even with input of the same current. As a result of this, in a case where the light-emission frequency of a specific pixel is high, the light-emission characteristics of the specific pixel deteriorate compared to other pixels, and an image having a disrupted white balance is displayed. The phenomenon in which the light-emission characteristics of a specific pixel deteriorate compared to other pixels is called “burn-in phenomenon.”
For example, Patent Document 1 discloses a method for converting luminance of images to retard progression of the degree of deterioration of light-emitting elements of pixel accompanying deterioration of characteristics over time, and prevent deterioration of white balance.
Patent Document 1
Japanese Patent Application Publication No. JP-A-2005-43776